1. Technical Field
The invention relates to acoustic musical instruments. More particularly, the invention relates to a suspended bracing system for acoustic musical instruments.
2. Description of the Prior Art
In an acoustic musical instrument, such as a guitar, bracing performs two different functions:                It strengthens the sound board of the instrument; and        It allows the sound board of the instrument to vibrate sufficiently to produce a warm and resonant tone.        
In a standard scale guitar having medium gauge strings, the guitar's sound board withstands approximately 185 lbs of constant tension. Tension must be considered both at those points where the sound board of the instrument joins the instrument body, and at that point where the sound board of the instrument supports the instrument bridge. A thin sound board that is not braced would buckle or warp in very little time. A sound board thick enough to withstand the pressure could not vibrate sufficiently and would result in a thin tone with little volume.
Bracing plays a major role in determining the tone of a guitar as well. See FIG. 1, for example, which is a plan view that shows a typical bracing pattern for a steel string acoustic guitar. Although there are many theories about tone production as related to bracing, there is little disagreement on its importance. A luthier makes purposeful decisions about the placement, pattern, and physical shape of bracing because, in many ways, these decisions affect the final tone of the instrument as much as the actual tone wood. For instance, Taylor Guitars' distinctive voice is heavily influenced by their bracing patterns. Likewise, vintage Martin guitars are prized for the shape of the braces and how they affect tone. It is well recognized that too much bracing produces a guitar that has a dead, muffled tone; while too little bracing results in poor structural integrity, as well as producing a guitar that has an airy tone with no definition.
The bracing pattern found in most steel-string dreadnoughts is the “X” pattern. Originally developed by C. F. Martin in the 1850's, this pattern features the two main braces running in an “X” from the upper bouts to the lower bouts. The “X” crosses somewhere between the sound hole and the bridge. There are several auxiliary braces other than the main X-braces. This pattern provides the strength and well-balanced tonal palette that most builders find attractive.
One problem with current bracing schemes for guitars and other acoustic instruments is that, while adding strength to the sound board of the instrument, even the most effective bracing currently used still necessarily diminishes the ability of the instrument sound board to vibrate. It would be advantageous to provide a bracing system for acoustic musical instruments that imparted necessary support to the sound board of the instrument, while minimizing interaction of the bracing with the sound board that reduces or interferes with the sound produced by the sound board of the instrument.